Alternating-current relay



June 1 1926. 1,586,549

J. R. FRY

ALTERNATING CURRENT RELAY Filed Mayll. 1922 outrun stares Parsnr Patented June 1, 1926.

isease JACOB R. FRY, OF NEW YORK, N. 'Y., ASSIGNOR 'IO WESTERN ELECTRIC COMPANY, IN-

CORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEWYORK. I

J ALTERNATING-C'EURRENT RELAY.

Application filed may 11, 1922. Serial No. 580,087.

alternating current relay which responds with certainty tocurrents of a desired frequency even though such currents be very feeble, but does not respond to aperiodic currents or currents of other frequencies.

Other objects of the invention are to improve the adjusting means for the pole pieces,. as well as the adjusting means for the contacts of a relay.

More specifically, the invention relates to an extremely sensitive alternating current relay of the vibrating reed type in which the vibrating reed is actuated by a pair of mag- "nets placed on either side of the free or vibrating end of the reed, Such a relay may be used to advantage on long telephone lines for signaling purposes, wherein the current is frequently much attenuated when it reaches a repeater or a terminal station, and consequently a very sensitive instrument is required to respond-thereto. The pole pieces and coils of the relay magnets are so mounted that the air gap between the poles may be varied to a very minute degree. This method of adjustment serves as a means for compensating "for the natural period of vibration of the reed, when, due to variations in its construction, its period is below or above the frequency to whichwhile Fig. 2 is a side elevation of the relay,

arts thereof being shown in section, and ig. .3 is a plan view, also partially in sec- .tion, of one end of the relay showing the means for adjusting the pole pieces and the contact members.

Referring to the drawings in detail a relay having a base plate 1 is yieldingly mounted upon a flanged sheet metal support 2 by means of rubber sponges 3. Two of these rubber sponges are held in alignment on either side of the metallic base 2 by means of cars 21 punched from the support 2, and are secured to the base plate 1 of the relay by means of a washer 22 and a stud screw 23 ,which terminates in the relay base 1. Two pairs of sponges complete the resilient mounting.

A terminal block 4 secured to one end of the ba'se2 1s provided with a series of plugs 5, thus adapting the relay for rack mounting, the rack (not shown) being provided with a plurality of jacks which are designed to receive the-plugs. A flange carrying a projecting portlon 6 is provided at the opposlte end of the base 2 to facilitate handng the relay.

bar or plate magnet 17, the other end ofwliich engages a groove 24 in the block 7. The magnet 17, which is in a magnetic circuit with the armature 8, is secured to the base plate 1- by means of stud screws 25.

The up-turned ends of U-shapedmember or bar 11, are bifurcated and are in addition provided with bearings to receive cylindrical pole pieces 13 upon which magnetizin coils 9 and 10- are mounted. An additiona bearing for the pole pieces is provided be tween the adjacent parallel brackets 14 secured to the bifurcated ends of the member 11. Adjusting members 15, consisting of wheels having holes punched in their peripheries to facilitate their turning,- are threaded to pole pieces 13 intermediate the up-turned ends of the member 11 and the parallel brackets 14. By rotating member 15, it is possible to vary the ositlon of the pole pieces '13 andto draw t e electromag netic coils toward or away from the upturned ends of the member 11. Inasmuch as the pole pieces 13 are held against rotation in their bearings in the member 11 by means neeenee to the reed when vibrating, -This adjusting means consists of a resilient spring 35, projections 36 thereon limiting the movement of the spring 26 in one direction and 6 an adjusting screw 27. "The resiliency of the spring 26 by itseli limits to a certain extent the amplitude of vibration ot the reed, while the relation of the make to the break period of the contact between the reed 8 and the spring 26 may be varied by theroperation of the screw 27.- The screw 27 may also be used for controlling the rela tion of the spring 26 to the reed 8 in such a manner as to permit'the reed to vibrate at its natural frequency with the least possible interference from spring 26. This latter adjustment may be of considerable importance when the operating characteristics of the reed are such as to make it particu- Qil larly sensitive to interference that may be caused by the amplitude limiting tendency of the spring 26. The adjustable screw .27 is held-in a bifurcated post 19 and locked thereto by means of an adjusting stud screw 20., An adjusting mob 28 has a calibrated periphery and has associated with it circumterential shield 29 which permits a reading of its adjustment. A second adjustable 31, serves as a back stop to limit the whip or temporary distortion or" the armature when a current impulse of excessive strength causes the relay to suddenly pull over its armature without vibrating it.

What is claimed is:

1. lln combination, a base, a block mounted thereupon at one end of said base, a supportihg means at the other end or" said base, a permanent bar magnet between said block and said supporting means, a tuned reed having one end thereof secured to said block, a pair of spaced magnetic cores mounted upon said supporting means and movable relatively thereto, said cores serving to actuate the free end of said reed, and means associated with said supporting means for adjusting the dis tance between said cores.

2. In combination, a base, ablock mounted on one end of said base, a supportin memmagnetic pole piece mounted on said support, a permanent magnet connecting said block and said supporting member, a vibrating armature parallel to said magnet fixed at one end to said block and with its free end in spaced relation to said pole piece, an adjusting means for said armature to limit the vibratory movement thereof, and an adjusting means for said pole iece to vary its position in relation to sai armature.

3. In combination, a base, a block mounted on one end of said base, a supporting member having two parallel arms mounted at the other end of said block, a pole piece screw 30 which is held in a bifurcated post her fixed at the other end of said 1856, a

secured to each of said arms, coils on said pole pieces, a permanent magnet connecting said block and said supporting member, a flexible reed fixed at one end to the block and with its tree end in a position between said pole pieces, means to regulate the vibratory movement of said reed between said pole pieces, and means to adjust the distance between the pole pieces and the reed.

l. ln combination, a base, a block mountd thereon, a supporting member having two parallel arms mounted on said base away from said block, a pole piece secured to "each of said arms, coils on said pole pieces, a permanent magnet connecting said block and said supporting member, a flexible reed fixed at one end to the block and with its free end extending between said pole pieces, means to regulate the vibratory movement of said reed between said poles pieces comprising a flexible contact and an adjusting means to regulate the tension thereof, and separate means for adjusting the distance between the pole pieces and the reed.

5. A relay comprising a base, a block mounted thereon, a comparatively long armature seoured at one end to said block in a position parallel to the base, a stationary support on said base adjacent the free end otthe armature, a permanent magnet of approximately the same length as the armature connecting the block and the support, and arranged in a position parallel to the base, a pole piece mounted upon said support in spaced relation to the free end of the arma- 109 ture, and means associated with said pole piece for varying the distance between the pole piece and the free end of the armature.

6. A relay comprising a base, a block mounted thereon, a comparatively long armature secured at one end to said block in a position parallel to the base, a stationary support on said base adjacent the free end of the armature, a permanent magnet of approximately the same length as the arma-' ture connecting the block and the support, and arranged in a position parallel to the base, a threaded pole piece mounted upon said support in spaced relation to the free end of the armature, and means cooperating with said threaded pole piece for varying the distance between the pole piece and the freeend of the armature.

7. A. relay comprising a base, a block mounted thereon, a comparatively long armature secured at one end to said block in a position parallel to the base, a unitary U- shaped bracket mounted upon said base adj acent the free end of the armature, apermanent magnet of approximately the same length as the armature connectingthe block and the bracket and located in a position parallel to the base, a pair of spaced magnetic cores mounted on said bracket and spaced from either side of the free end of Leaaaee said armature, coils upon each of said cores, and means fOr shiftingsaid cores to vary the distance between them.

8. A relay comprising a base, a block mounted thereon, a comparatively long tuned reed secured at one end to said block in a position parallel to the base, a unitary U- shaped bracket upon said base adjacent the free end of the reed, a permanent magnet of approximately the samelength as the reed connecting the block and the bracket and located in a position parallel to the base, a

pair of spaced electrically energized mag netic cores mounted on said bracket and spaced from either 'side of the free end of my name this tthday of May, A. D. 1929;.

JACOB R. FRY. 

